Investigators say Nathan Luna, 34, was dragged to shore by his six-year-old daughter. The incident happened near 144th Avenue and 66th Street in Laketown Township.

Luna was an Assistant Principal at South Haven High School. Michigan State Police say there was only about three feet of water when Luna jumped from the boat.

"From the injury it would show us he dove head first and either struck the bottom or struck a rock to cause that fracture in the upper neck," says Detective Matthew Doan with the Michigan State Police.

Authorities say further investigation is needed to determine whether the broken neck or drowning led to Luna's death.